linux_dsm_epyc7002/arch/powerpc/platforms/pseries/setup.c
Paul Mackerras a6dbf93a2a powerpc: Fix bug where perf_counters breaks oprofile
Currently there is a bug where if you use oprofile on a pSeries
machine, then use perf_counters, then use oprofile again, oprofile
will not work correctly; it will lose the PMU configuration the next
time the hypervisor does a partition context switch, and thereafter
won't count anything.

Maynard Johnson identified the sequence causing the problem:
- oprofile setup calls ppc_enable_pmcs(), which calls
  pseries_lpar_enable_pmcs, which tells the hypervisor that we want
  to use the PMU, and sets the "PMU in use" flag in the lppaca.
  This flag tells the hypervisor whether it needs to save and restore
  the PMU config.
- The perf_counter code sets and clears the "PMU in use" flag directly
  as it context-switches the PMU between tasks, and leaves it clear
  when it finishes.
- oprofile setup, called for a new oprofile run, calls ppc_enable_pmcs,
  which does nothing because it has already been called.  In particular
  it doesn't set the "PMU in use" flag.

This fixes the problem by arranging for ppc_enable_pmcs to always set
the "PMU in use" flag.  It makes the perf_counter code call
ppc_enable_pmcs also rather than calling the lower-level function
directly, and removes the setting of the "PMU in use" flag from
pseries_lpar_enable_pmcs, since that is now done in its caller.

This also removes the declaration of pasemi_enable_pmcs because it
isn't defined anywhere.

Reported-by: Maynard Johnson <mpjohn@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: <stable@kernel.org)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-09-11 11:27:58 +10:00

633 lines
16 KiB
C

/*
* 64-bit pSeries and RS/6000 setup code.
*
* Copyright (C) 1995 Linus Torvalds
* Adapted from 'alpha' version by Gary Thomas
* Modified by Cort Dougan (cort@cs.nmt.edu)
* Modified by PPC64 Team, IBM Corp
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
/*
* bootup setup stuff..
*/
#include <linux/cpu.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/tty.h>
#include <linux/major.h>
#include <linux/interrupt.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/console.h>
#include <linux/pci.h>
#include <linux/utsname.h>
#include <linux/adb.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/seq_file.h>
#include <linux/root_dev.h>
#include <asm/mmu.h>
#include <asm/processor.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/prom.h>
#include <asm/rtas.h>
#include <asm/pci-bridge.h>
#include <asm/iommu.h>
#include <asm/dma.h>
#include <asm/machdep.h>
#include <asm/irq.h>
#include <asm/time.h>
#include <asm/nvram.h>
#include "xics.h"
#include <asm/pmc.h>
#include <asm/mpic.h>
#include <asm/ppc-pci.h>
#include <asm/i8259.h>
#include <asm/udbg.h>
#include <asm/smp.h>
#include <asm/firmware.h>
#include <asm/eeh.h>
#include <asm/pSeries_reconfig.h>
#include "plpar_wrappers.h"
#include "pseries.h"
int CMO_PrPSP = -1;
int CMO_SecPSP = -1;
unsigned long CMO_PageSize = (ASM_CONST(1) << IOMMU_PAGE_SHIFT);
EXPORT_SYMBOL(CMO_PageSize);
int fwnmi_active; /* TRUE if an FWNMI handler is present */
static void pseries_shared_idle_sleep(void);
static void pseries_dedicated_idle_sleep(void);
static struct device_node *pSeries_mpic_node;
static void pSeries_show_cpuinfo(struct seq_file *m)
{
struct device_node *root;
const char *model = "";
root = of_find_node_by_path("/");
if (root)
model = of_get_property(root, "model", NULL);
seq_printf(m, "machine\t\t: CHRP %s\n", model);
of_node_put(root);
}
/* Initialize firmware assisted non-maskable interrupts if
* the firmware supports this feature.
*/
static void __init fwnmi_init(void)
{
unsigned long system_reset_addr, machine_check_addr;
int ibm_nmi_register = rtas_token("ibm,nmi-register");
if (ibm_nmi_register == RTAS_UNKNOWN_SERVICE)
return;
/* If the kernel's not linked at zero we point the firmware at low
* addresses anyway, and use a trampoline to get to the real code. */
system_reset_addr = __pa(system_reset_fwnmi) - PHYSICAL_START;
machine_check_addr = __pa(machine_check_fwnmi) - PHYSICAL_START;
if (0 == rtas_call(ibm_nmi_register, 2, 1, NULL, system_reset_addr,
machine_check_addr))
fwnmi_active = 1;
}
static void pseries_8259_cascade(unsigned int irq, struct irq_desc *desc)
{
unsigned int cascade_irq = i8259_irq();
if (cascade_irq != NO_IRQ)
generic_handle_irq(cascade_irq);
desc->chip->eoi(irq);
}
static void __init pseries_setup_i8259_cascade(void)
{
struct device_node *np, *old, *found = NULL;
unsigned int cascade;
const u32 *addrp;
unsigned long intack = 0;
int naddr;
for_each_node_by_type(np, "interrupt-controller") {
if (of_device_is_compatible(np, "chrp,iic")) {
found = np;
break;
}
}
if (found == NULL) {
printk(KERN_DEBUG "pic: no ISA interrupt controller\n");
return;
}
cascade = irq_of_parse_and_map(found, 0);
if (cascade == NO_IRQ) {
printk(KERN_ERR "pic: failed to map cascade interrupt");
return;
}
pr_debug("pic: cascade mapped to irq %d\n", cascade);
for (old = of_node_get(found); old != NULL ; old = np) {
np = of_get_parent(old);
of_node_put(old);
if (np == NULL)
break;
if (strcmp(np->name, "pci") != 0)
continue;
addrp = of_get_property(np, "8259-interrupt-acknowledge", NULL);
if (addrp == NULL)
continue;
naddr = of_n_addr_cells(np);
intack = addrp[naddr-1];
if (naddr > 1)
intack |= ((unsigned long)addrp[naddr-2]) << 32;
}
if (intack)
printk(KERN_DEBUG "pic: PCI 8259 intack at 0x%016lx\n", intack);
i8259_init(found, intack);
of_node_put(found);
set_irq_chained_handler(cascade, pseries_8259_cascade);
}
static void __init pseries_mpic_init_IRQ(void)
{
struct device_node *np;
const unsigned int *opprop;
unsigned long openpic_addr = 0;
int naddr, n, i, opplen;
struct mpic *mpic;
np = of_find_node_by_path("/");
naddr = of_n_addr_cells(np);
opprop = of_get_property(np, "platform-open-pic", &opplen);
if (opprop != 0) {
openpic_addr = of_read_number(opprop, naddr);
printk(KERN_DEBUG "OpenPIC addr: %lx\n", openpic_addr);
}
of_node_put(np);
BUG_ON(openpic_addr == 0);
/* Setup the openpic driver */
mpic = mpic_alloc(pSeries_mpic_node, openpic_addr,
MPIC_PRIMARY,
16, 250, /* isu size, irq count */
" MPIC ");
BUG_ON(mpic == NULL);
/* Add ISUs */
opplen /= sizeof(u32);
for (n = 0, i = naddr; i < opplen; i += naddr, n++) {
unsigned long isuaddr = of_read_number(opprop + i, naddr);
mpic_assign_isu(mpic, n, isuaddr);
}
/* All ISUs are setup, complete initialization */
mpic_init(mpic);
/* Look for cascade */
pseries_setup_i8259_cascade();
}
static void __init pseries_xics_init_IRQ(void)
{
xics_init_IRQ();
pseries_setup_i8259_cascade();
}
static void pseries_lpar_enable_pmcs(void)
{
unsigned long set, reset;
set = 1UL << 63;
reset = 0;
plpar_hcall_norets(H_PERFMON, set, reset);
}
static void __init pseries_discover_pic(void)
{
struct device_node *np;
const char *typep;
for (np = NULL; (np = of_find_node_by_name(np,
"interrupt-controller"));) {
typep = of_get_property(np, "compatible", NULL);
if (strstr(typep, "open-pic")) {
pSeries_mpic_node = of_node_get(np);
ppc_md.init_IRQ = pseries_mpic_init_IRQ;
ppc_md.get_irq = mpic_get_irq;
setup_kexec_cpu_down_mpic();
smp_init_pseries_mpic();
return;
} else if (strstr(typep, "ppc-xicp")) {
ppc_md.init_IRQ = pseries_xics_init_IRQ;
setup_kexec_cpu_down_xics();
smp_init_pseries_xics();
return;
}
}
printk(KERN_ERR "pSeries_discover_pic: failed to recognize"
" interrupt-controller\n");
}
static int pci_dn_reconfig_notifier(struct notifier_block *nb, unsigned long action, void *node)
{
struct device_node *np = node;
struct pci_dn *pci = NULL;
int err = NOTIFY_OK;
switch (action) {
case PSERIES_RECONFIG_ADD:
pci = np->parent->data;
if (pci)
update_dn_pci_info(np, pci->phb);
break;
default:
err = NOTIFY_DONE;
break;
}
return err;
}
static struct notifier_block pci_dn_reconfig_nb = {
.notifier_call = pci_dn_reconfig_notifier,
};
static void __init pSeries_setup_arch(void)
{
/* Discover PIC type and setup ppc_md accordingly */
pseries_discover_pic();
/* openpic global configuration register (64-bit format). */
/* openpic Interrupt Source Unit pointer (64-bit format). */
/* python0 facility area (mmio) (64-bit format) REAL address. */
/* init to some ~sane value until calibrate_delay() runs */
loops_per_jiffy = 50000000;
fwnmi_init();
/* Find and initialize PCI host bridges */
init_pci_config_tokens();
find_and_init_phbs();
pSeries_reconfig_notifier_register(&pci_dn_reconfig_nb);
eeh_init();
pSeries_nvram_init();
/* Choose an idle loop */
if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
vpa_init(boot_cpuid);
if (get_lppaca()->shared_proc) {
printk(KERN_DEBUG "Using shared processor idle loop\n");
ppc_md.power_save = pseries_shared_idle_sleep;
} else {
printk(KERN_DEBUG "Using dedicated idle loop\n");
ppc_md.power_save = pseries_dedicated_idle_sleep;
}
} else {
printk(KERN_DEBUG "Using default idle loop\n");
}
if (firmware_has_feature(FW_FEATURE_LPAR))
ppc_md.enable_pmcs = pseries_lpar_enable_pmcs;
else
ppc_md.enable_pmcs = power4_enable_pmcs;
}
static int __init pSeries_init_panel(void)
{
/* Manually leave the kernel version on the panel. */
ppc_md.progress("Linux ppc64\n", 0);
ppc_md.progress(init_utsname()->version, 0);
return 0;
}
arch_initcall(pSeries_init_panel);
static int pseries_set_dabr(unsigned long dabr)
{
return plpar_hcall_norets(H_SET_DABR, dabr);
}
static int pseries_set_xdabr(unsigned long dabr)
{
/* We want to catch accesses from kernel and userspace */
return plpar_hcall_norets(H_SET_XDABR, dabr,
H_DABRX_KERNEL | H_DABRX_USER);
}
#define CMO_CHARACTERISTICS_TOKEN 44
#define CMO_MAXLENGTH 1026
/**
* fw_cmo_feature_init - FW_FEATURE_CMO is not stored in ibm,hypertas-functions,
* handle that here. (Stolen from parse_system_parameter_string)
*/
void pSeries_cmo_feature_init(void)
{
char *ptr, *key, *value, *end;
int call_status;
int page_order = IOMMU_PAGE_SHIFT;
pr_debug(" -> fw_cmo_feature_init()\n");
spin_lock(&rtas_data_buf_lock);
memset(rtas_data_buf, 0, RTAS_DATA_BUF_SIZE);
call_status = rtas_call(rtas_token("ibm,get-system-parameter"), 3, 1,
NULL,
CMO_CHARACTERISTICS_TOKEN,
__pa(rtas_data_buf),
RTAS_DATA_BUF_SIZE);
if (call_status != 0) {
spin_unlock(&rtas_data_buf_lock);
pr_debug("CMO not available\n");
pr_debug(" <- fw_cmo_feature_init()\n");
return;
}
end = rtas_data_buf + CMO_MAXLENGTH - 2;
ptr = rtas_data_buf + 2; /* step over strlen value */
key = value = ptr;
while (*ptr && (ptr <= end)) {
/* Separate the key and value by replacing '=' with '\0' and
* point the value at the string after the '='
*/
if (ptr[0] == '=') {
ptr[0] = '\0';
value = ptr + 1;
} else if (ptr[0] == '\0' || ptr[0] == ',') {
/* Terminate the string containing the key/value pair */
ptr[0] = '\0';
if (key == value) {
pr_debug("Malformed key/value pair\n");
/* Never found a '=', end processing */
break;
}
if (0 == strcmp(key, "CMOPageSize"))
page_order = simple_strtol(value, NULL, 10);
else if (0 == strcmp(key, "PrPSP"))
CMO_PrPSP = simple_strtol(value, NULL, 10);
else if (0 == strcmp(key, "SecPSP"))
CMO_SecPSP = simple_strtol(value, NULL, 10);
value = key = ptr + 1;
}
ptr++;
}
/* Page size is returned as the power of 2 of the page size,
* convert to the page size in bytes before returning
*/
CMO_PageSize = 1 << page_order;
pr_debug("CMO_PageSize = %lu\n", CMO_PageSize);
if (CMO_PrPSP != -1 || CMO_SecPSP != -1) {
pr_info("CMO enabled\n");
pr_debug("CMO enabled, PrPSP=%d, SecPSP=%d\n", CMO_PrPSP,
CMO_SecPSP);
powerpc_firmware_features |= FW_FEATURE_CMO;
} else
pr_debug("CMO not enabled, PrPSP=%d, SecPSP=%d\n", CMO_PrPSP,
CMO_SecPSP);
spin_unlock(&rtas_data_buf_lock);
pr_debug(" <- fw_cmo_feature_init()\n");
}
/*
* Early initialization. Relocation is on but do not reference unbolted pages
*/
static void __init pSeries_init_early(void)
{
pr_debug(" -> pSeries_init_early()\n");
if (firmware_has_feature(FW_FEATURE_LPAR))
find_udbg_vterm();
if (firmware_has_feature(FW_FEATURE_DABR))
ppc_md.set_dabr = pseries_set_dabr;
else if (firmware_has_feature(FW_FEATURE_XDABR))
ppc_md.set_dabr = pseries_set_xdabr;
pSeries_cmo_feature_init();
iommu_init_early_pSeries();
pr_debug(" <- pSeries_init_early()\n");
}
/*
* Called very early, MMU is off, device-tree isn't unflattened
*/
static int __init pSeries_probe_hypertas(unsigned long node,
const char *uname, int depth,
void *data)
{
const char *hypertas;
unsigned long len;
if (depth != 1 ||
(strcmp(uname, "rtas") != 0 && strcmp(uname, "rtas@0") != 0))
return 0;
hypertas = of_get_flat_dt_prop(node, "ibm,hypertas-functions", &len);
if (!hypertas)
return 1;
powerpc_firmware_features |= FW_FEATURE_LPAR;
fw_feature_init(hypertas, len);
return 1;
}
static int __init pSeries_probe(void)
{
unsigned long root = of_get_flat_dt_root();
char *dtype = of_get_flat_dt_prop(root, "device_type", NULL);
if (dtype == NULL)
return 0;
if (strcmp(dtype, "chrp"))
return 0;
/* Cell blades firmware claims to be chrp while it's not. Until this
* is fixed, we need to avoid those here.
*/
if (of_flat_dt_is_compatible(root, "IBM,CPBW-1.0") ||
of_flat_dt_is_compatible(root, "IBM,CBEA"))
return 0;
pr_debug("pSeries detected, looking for LPAR capability...\n");
/* Now try to figure out if we are running on LPAR */
of_scan_flat_dt(pSeries_probe_hypertas, NULL);
if (firmware_has_feature(FW_FEATURE_LPAR))
hpte_init_lpar();
else
hpte_init_native();
pr_debug("Machine is%s LPAR !\n",
(powerpc_firmware_features & FW_FEATURE_LPAR) ? "" : " not");
return 1;
}
DECLARE_PER_CPU(unsigned long, smt_snooze_delay);
static void pseries_dedicated_idle_sleep(void)
{
unsigned int cpu = smp_processor_id();
unsigned long start_snooze;
unsigned long in_purr, out_purr;
/*
* Indicate to the HV that we are idle. Now would be
* a good time to find other work to dispatch.
*/
get_lppaca()->idle = 1;
get_lppaca()->donate_dedicated_cpu = 1;
in_purr = mfspr(SPRN_PURR);
/*
* We come in with interrupts disabled, and need_resched()
* has been checked recently. If we should poll for a little
* while, do so.
*/
if (__get_cpu_var(smt_snooze_delay)) {
start_snooze = get_tb() +
__get_cpu_var(smt_snooze_delay) * tb_ticks_per_usec;
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
while (get_tb() < start_snooze) {
if (need_resched() || cpu_is_offline(cpu))
goto out;
ppc64_runlatch_off();
HMT_low();
HMT_very_low();
}
HMT_medium();
clear_thread_flag(TIF_POLLING_NRFLAG);
smp_mb();
local_irq_disable();
if (need_resched() || cpu_is_offline(cpu))
goto out;
}
cede_processor();
out:
HMT_medium();
out_purr = mfspr(SPRN_PURR);
get_lppaca()->wait_state_cycles += out_purr - in_purr;
get_lppaca()->donate_dedicated_cpu = 0;
get_lppaca()->idle = 0;
}
static void pseries_shared_idle_sleep(void)
{
/*
* Indicate to the HV that we are idle. Now would be
* a good time to find other work to dispatch.
*/
get_lppaca()->idle = 1;
/*
* Yield the processor to the hypervisor. We return if
* an external interrupt occurs (which are driven prior
* to returning here) or if a prod occurs from another
* processor. When returning here, external interrupts
* are enabled.
*/
cede_processor();
get_lppaca()->idle = 0;
}
static int pSeries_pci_probe_mode(struct pci_bus *bus)
{
if (firmware_has_feature(FW_FEATURE_LPAR))
return PCI_PROBE_DEVTREE;
return PCI_PROBE_NORMAL;
}
/**
* pSeries_power_off - tell firmware about how to power off the system.
*
* This function calls either the power-off rtas token in normal cases
* or the ibm,power-off-ups token (if present & requested) in case of
* a power failure. If power-off token is used, power on will only be
* possible with power button press. If ibm,power-off-ups token is used
* it will allow auto poweron after power is restored.
*/
static void pSeries_power_off(void)
{
int rc;
int rtas_poweroff_ups_token = rtas_token("ibm,power-off-ups");
if (rtas_flash_term_hook)
rtas_flash_term_hook(SYS_POWER_OFF);
if (rtas_poweron_auto == 0 ||
rtas_poweroff_ups_token == RTAS_UNKNOWN_SERVICE) {
rc = rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1);
printk(KERN_INFO "RTAS power-off returned %d\n", rc);
} else {
rc = rtas_call(rtas_poweroff_ups_token, 0, 1, NULL);
printk(KERN_INFO "RTAS ibm,power-off-ups returned %d\n", rc);
}
for (;;);
}
#ifndef CONFIG_PCI
void pSeries_final_fixup(void) { }
#endif
define_machine(pseries) {
.name = "pSeries",
.probe = pSeries_probe,
.setup_arch = pSeries_setup_arch,
.init_early = pSeries_init_early,
.show_cpuinfo = pSeries_show_cpuinfo,
.log_error = pSeries_log_error,
.pcibios_fixup = pSeries_final_fixup,
.pci_probe_mode = pSeries_pci_probe_mode,
.restart = rtas_restart,
.power_off = pSeries_power_off,
.halt = rtas_halt,
.panic = rtas_os_term,
.get_boot_time = rtas_get_boot_time,
.get_rtc_time = rtas_get_rtc_time,
.set_rtc_time = rtas_set_rtc_time,
.calibrate_decr = generic_calibrate_decr,
.progress = rtas_progress,
.system_reset_exception = pSeries_system_reset_exception,
.machine_check_exception = pSeries_machine_check_exception,
};